Lamination is a commonly used method for protecting and preserving flat sheet articles such as paper documents and photos. Thermal laminators utilize heat to laminate the sheet article between pieces of protective film. Typically, a lamination pouch comprising a heat curable adhesive-backed film that is sealed on one edge is utilized. A sheet article to be preserved is placed in the lamination pouch and the pouch is fed between a pair of heated rollers, which compress the pouch and activate the adhesive.
The sealed edge of the lamination pouch is intended to be the leading edge of the pouch as it is fed into the laminator to ensure that the lamination pouch does not adhere to the roller during lamination. Many laminator users, however, mistakenly feed the pouch into the laminator backwards. In addition, some laminator users cut the lamination pouch (for example, to customize the size of the pouch) prior to insertion into the laminator. In both of these situations, adhesive may be left exposed or may be squeezed out along the leading edge. The leading edge may therefore stick to one of the rollers and wrap around the roller causing the laminator to jam.
Various approaches have been utilized to address the problem of thermal laminator jamming. For example, U.S. Pat. No. 7,886,792 discloses incorporating a sensing element beside the roller for detecting jamming and reversely rotating the roller to eject a jammed sheet article. U.S. Pat. No. 7,832,445 discloses using a set of blade members positioned on the exit side of the rollers for preventing the lamination pouch from passing between the roller and the blade members.